Yeah, procrastination ahoy! I know exactly what you mean.

Another example: People keep asking me how many exams I will take at the (quickly approaching!) end of this term and I can only shrug my shoulders and answer: "How should I know?"
Because if there are more dates offered for the same exam I always decide like two days (or three, mostly) in advance if I'm definatley going to take it, and often start studying only one day before. Same with homeworks.
If I have fixed dates I'm always panicky and complaining long before it's due and put off the work nontheless.